[libc-commits] [libc] f0e100a - [amdgpu][openmp] Treat missing TIMESTAMP_FREQUENCY as non-fatal (#70987)

[via libc-commits]

Author: Jon Chesterfield
Date: 2023-11-01T22:43:34Z
New Revision: f0e100a05acbe895a7a3e76b4713d2f740fe8463

URL: https://github.com/llvm/llvm-project/commit/f0e100a05acbe895a7a3e76b4713d2f740fe8463
DIFF: https://github.com/llvm/llvm-project/commit/f0e100a05acbe895a7a3e76b4713d2f740fe8463.diff

LOG: [amdgpu][openmp] Treat missing TIMESTAMP_FREQUENCY as non-fatal (#70987)

If you build with dynamic_hsa, the symbol is known and compilation
succeeds. If you then run with a slightly older libhsa, this argument is
not recognised and an error returned. I'd rather the program runs with a
misleading omp wtime than refuses to run at all.

Added: 
    

Modified: 
    libc/utils/gpu/loader/amdgpu/Loader.cpp
    openmp/libomptarget/plugins-nextgen/amdgpu/src/rtl.cpp

Removed: 
    


################################################################################
diff  --git a/libc/utils/gpu/loader/amdgpu/Loader.cpp b/libc/utils/gpu/loader/amdgpu/Loader.cpp
index 2f99076a720e2aa..b1b3aa6ce028ca5 100644
--- a/libc/utils/gpu/loader/amdgpu/Loader.cpp
+++ b/libc/utils/gpu/loader/amdgpu/Loader.cpp
@@ -487,21 +487,22 @@ int load(int argc, char **argv, char **envp, void *image, size_t size,
       handle_error(err);
     hsa_amd_agents_allow_access(1, &dev_agent, nullptr, host_clock_freq);
 
-    if (hsa_status_t err =
-            hsa_agent_get_info(dev_agent,
-                               static_cast<hsa_agent_info_t>(
-                                   HSA_AMD_AGENT_INFO_TIMESTAMP_FREQUENCY),
-                               host_clock_freq))
-      handle_error(err);
-
-    void *freq_addr;
-    if (hsa_status_t err = hsa_executable_symbol_get_info(
-            freq_sym, HSA_EXECUTABLE_SYMBOL_INFO_VARIABLE_ADDRESS, &freq_addr))
-      handle_error(err);
-
-    if (hsa_status_t err = hsa_memcpy(freq_addr, dev_agent, host_clock_freq,
-                                      host_agent, sizeof(uint64_t)))
-      handle_error(err);
+    if (HSA_STATUS_SUCCESS ==
+        hsa_agent_get_info(dev_agent,
+                           static_cast<hsa_agent_info_t>(
+                               HSA_AMD_AGENT_INFO_TIMESTAMP_FREQUENCY),
+                           host_clock_freq)) {
+
+      void *freq_addr;
+      if (hsa_status_t err = hsa_executable_symbol_get_info(
+              freq_sym, HSA_EXECUTABLE_SYMBOL_INFO_VARIABLE_ADDRESS,
+              &freq_addr))
+        handle_error(err);
+
+      if (hsa_status_t err = hsa_memcpy(freq_addr, dev_agent, host_clock_freq,
+                                        host_agent, sizeof(uint64_t)))
+        handle_error(err);
+    }
   }
 
   // Obtain a queue with the minimum (power of two) size, used to send commands

diff  --git a/openmp/libomptarget/plugins-nextgen/amdgpu/src/rtl.cpp b/openmp/libomptarget/plugins-nextgen/amdgpu/src/rtl.cpp
index 71207f767fdcc60..378cad8f8ca4f15 100644
--- a/openmp/libomptarget/plugins-nextgen/amdgpu/src/rtl.cpp
+++ b/openmp/libomptarget/plugins-nextgen/amdgpu/src/rtl.cpp
@@ -1810,10 +1810,12 @@ struct AMDGPUDeviceTy : public GenericDeviceTy, AMDGenericDeviceTy {
       return Err;
     GridValues.GV_Warp_Size = WavefrontSize;
 
-    // Get the frequency of the steady clock.
-    if (auto Err = getDeviceAttr(HSA_AMD_AGENT_INFO_TIMESTAMP_FREQUENCY,
-                                 ClockFrequency))
-      return Err;
+    // Get the frequency of the steady clock. If the attribute is missing
+    // assume running on an older libhsa and default to 0, omp_get_wtime
+    // will be inaccurate but otherwise programs can still run.
+    if (auto Err = getDeviceAttrRaw(HSA_AMD_AGENT_INFO_TIMESTAMP_FREQUENCY,
+                                    ClockFrequency))
+      ClockFrequency = 0;
 
     // Load the grid values dependending on the wavefront.
     if (WavefrontSize == 32)